Immunoassay method and assay reagent used in said method

Abstract

A problem to be solved by the invention is to provide a method of avoiding an influence of hemoglobin in an immunological measurement method for an analyte in a biological sample. The problem is solved by reacting a sample suspected of containing an analyte with an antibody binding to the analyte in the presence of a polypeptide consisting of amino acids No. 419 to No. 607 of the amino acid sequence of DnaK, a heat shock protein (HSP), derived from E. coli as set forth in SEQ ID NO: 1 or a polypeptide having at least 90% sequence identity with the polypeptide.

1 . An immunoassay for an analyte in a sample containing hemoglobin, comprising: reacting an analyte in a sample suspected of being present in the sample containing hemoglobin with an antibody binding to the analyte in the presence of a polypeptide consisting of amino acids No. 419 to No. 607 of the amino acid sequence of DnaK, a heat shock protein (HSP), derived from  E. coli  as set forth in SEQ ID NO: 1 or a polypeptide having at least 90% sequence identity with the polypeptide. 
     
     
         2 . The method according to  claim 1 , wherein the analyte in a sample containing hemoglobin is reacted with an antibody binding to the analyte also in the presence of one or more buffer components selected from HEPES, Bis-Tris, TES, and Tris. 
     
     
         3 . The method according to  claim 1 , wherein the antibody is immobilized on an insoluble carrier. 
     
     
         4 . The method according to  claim 3 , wherein the insoluble carrier is latex particles or metal colloid particles. 
     
     
         5 . The method according to  claim 4 , wherein a particle agglutination measurement method is utilized. 
     
     
         6 . The method according to any of  claim 1 , wherein the antibody is two or more monoclonal antibodies having recognition sites different from each other. 
     
     
         7 . The method according to  claim 6 , wherein the two or more monoclonal antibodies having recognition sites different from each other are respectively immobilized on the latex particles, and wherein the analyte in the sample is detected by a latex turbidimetric immunoassay. 
     
     
         8 . The method according to  claim 1 , wherein the sample is urine, whole blood, serum, or plasma. 
     
     
         9 . The method according to  claim 1 , wherein the analyte is L-FABP (liver-type fatty acid binding protein). 
     
     
         10 . A method of avoiding an influence of hemoglobin in a method of detecting an analyte in a sample containing hemoglobin with an antibody binding to the analyte, the method comprising:
 reacting a sample suspected of containing the analyte with an antibody binding to the analyte   
       in the presence of a polypeptide consisting of amino acids No. 419 to No. 607 of the amino acid sequence of DnaK, a heat shock protein (HSP), derived from  E. coli  as set forth in SEQ ID NO: 1 or a polypeptide having at least 90% sequence identity with the polypeptide. 
     
     
         11 . The method according to  claim 2 , wherein the antibody is immobilized on an insoluble carrier. 
     
     
         12 . The method according to  claim 2 , wherein the antibody is two or more monoclonal antibodies having recognition sites different from each other. 
     
     
         13 . The method according to  claim 3 , wherein the antibody is two or more monoclonal antibodies having recognition sites different from each other. 
     
     
         14 . The method according to  claim 4 , wherein the antibody is two or more monoclonal antibodies having recognition sites different from each other. 
     
     
         15 . The method according to  claim 5 , wherein the antibody is two or more monoclonal antibodies having recognition sites different from each other. 
     
     
         16 . The method according to  claim 2 , wherein the sample is urine, whole blood, serum, or plasma. 
     
     
         17 . The method according to  claim 3 , wherein the sample is urine, whole blood, serum, or plasma. 
     
     
         18 . The method according to  claim 4 , wherein the sample is urine, whole blood, serum, or plasma. 
     
     
         19 . The method according to  claim 5 , wherein the sample is urine, whole blood, serum, or plasma. 
     
     
         20 . The method according to  claim 6 , wherein the sample is urine, whole blood, serum, or plasma.